Self-generated interference in radio-frequency (RF) receivers is the general result of signals interacting with circuit block nonidealities in such a way that error terms arise and corrupt the desired signal intended for reception. This interference is sometimes so severe that even increasing the circuit area and power dissipation arbitrarily to reduce the nonidealities is insufficient, and costly off-chip components are required for the receiver to meet desired specifications. Often, self-generated interference manifests itself as distortion products due to circuit block nonlinearities. Self-generated interference can also arise due to I-Q mismatch, interstage coupling, or various other mechanisms.
Self-generated interference problems, such as discussed above, worsen in general as CMOS processes continue to scale smaller. Also, as supply voltages drop, less headroom is available to apply large overdrive bias voltages to devices, worsening their linearity and matching properties. Furthermore, as market pressures demand the further reduction in the number and size of off-chip components, auxiliary blocks that once facilitated receiver design, such as off-chip SAW filters, will become extinct.
There is a need for monolithic solutions to minimize self-generated interference in RF receivers.